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History

1884

discovered by Gregor Žiberna.

1885

Žiberna is allowed to develop the cave and live in a small house at the entrance.

1887

opened to the public, operated by the Österreichischer Touristenclub (Austrian Tourist Association).

1887

visited by the Crown Prince of the Austrio-Hungarian Empire, Rudolf von Habsburg and named after him.

cave entrance blasted by the German Wehrmacht to make sure the cave was not used by partisans.

1987

cave reopened to the public, but only with the historic trail and no light, open on Sundays.

Description

Divaška Jama is one of the historic show caves of the classical karst.
Located near the town Divača, it was named after this town.
It was discovered in 1884 by Gregor Žiberna, a local caver, and was opened to the public after only three years.
Soon it was visited by the high society of the turn of the century, for example the Crown Prince of the Austrio-Hungarian Empire, Rudolf von Habsburg visited the cave in the first year.
The cave was even named Kronprinz Rudolf Grotte or in Slowenian Rudolfova Vilenica after his visit.

One of the main reasons for the popularity of the cave was the nearby train station, which allowed people to take a day trip from Trieste.
The so-called Südbahn (southern train route) connects Vienna with Trieste, which was the only access to the sea for the landlocked Austrio-Hungarian Empire.
It was inaugurated on 27-JUL-1857, and Divača was the station on top of the karst mountain ridge.
The trains from Trieste had to ascend from 3m a.s.l. at Trieste Centrale station to 435m a.s.l. at Divača, on a quite short route of only about 15 kilometers.
At Divača the steam engines needed a refill of water and coal.
Also the ash and cinder of the coal had to be removed, and so a canal was built into the entrance of a nearby doline and the ash was flushed down this canal.
This was actually the doline where later the Divaška Jama was discovered.
Until today you can see the black grime in the entrance area, which is a result of dumping the ash into the cave.
There are also some remains of the canal at the wall of the doline.
However, there is another version of the story which says that the first trails were built using the cinder because it was cheap and coal dust to make sure it was not slippery.
As a result the cave was covered by the black dust which was whirled up by the visitors.

The cave is visited on a trail which goes down along the wall of the doline to an artificial entrance.
On its way you can see the natural entrance, which is where the cave was discovered.
Behind this natural entrance is a drop of some 20m into the first chamber, you can see the path deep below.
After you have descended to the level of the cave passage, the cave is mostly horizontal.
Still the trails goes up and down continually, mostly because of huge collapses of the cave ceiling.
The cave has an abundance of speleothms, mostly stalactites and stalagmites.
Huge stalagmites can be up to 12m high.
There is only one passage with one trail, so at the end the visitors turns around and return on the same trail.

The cave temperature is given with 8°C to 11°C.
This requires some further explanation, as the cave actually has a constant temperature of 11°C throughout the main passage.
But the doline is a depression, and in winter cold air, which is heavier than warm air, flows into the doline, and through cracks it enters the first section of the cave.
As a result this entrance section, the chamber called Plesna dvorana (dance hall) has only around 8°C, and this temperature is not constant, it depends on the outside temperatures during winter.
But after the first chamber a first ascend leads to a natural bridge and the Soteska šipka (Rosehip Groge) which blocks the cold air from entering the rest of the cave.

After its early success the cave was popular until the begin of the 20th century.
During World War I the frontline was very close and so the cave was abandoned.
After the lost war this area became part of Italy, the border was now between Postojna and Planina.
Reopened between the wars it was renamed Grotta Umberto Sotto Corona after an Italian caver.
But there was no operator any more and after Žiberna died in 1929 the cave was forgotten.
It was closed during World War II, when the Germans and Italians roamed the area.
In 1943 the entrance was blasted by the German Wehrmacht to make sure the cave was not used by partisans.
During socialist times it stayed closed, as there were now several more interesting show caves in the area.

Finally in the 1980s the local caving club took responsibility of the cave and reopened it in 1987 for special tours after appointment only.
They started to renovate the trails and later the cave was opened on Sundays, still without electric light.
The newest developent are new trails and electric light plus regular guided tours.
At the moment [2018] about 500m of the trail is renovated using a special non-slip concrete and the first part of the cave is equipped with modern LED light.
They even started to clean the black grime from the steam engines.
The rest of the cave is still in its former state and has no light, it is shown only on special tours.
There is a trail, sometimes paved, sometimes compressed cave floor, but no light.
The caving club is named Jamarsko Društvo Gregor Žiberna Divača (Caving Club Gregor Žiberna), named after the discoverer of the cave.
Beneath the show cave they also do research in several caves of the area.

Gregor Žiberna (1855—1929), nicknamed Tentava, explored several caves in the area around Divača.
He was a butcher and produced the local specialty, smoked sausages.
With his brother Nacet he operated the first Slovenian cafe at Trieste, but they were expelled by the Italian nacionalists which were called Irredenters.
So they returned to their home town Divača.
Tentava did not have permanent employment, he was doing various things like hunting snakes for museums to earn some money.
And he was an early speleologist exploring caves for knowledge together with his friend Jakob Rešaver.
As was quite common for Slowenes of this time, he was speaking fluent Italian and German, so he was doing guided tours in three languages.
The most important and difficult cave he explored was nearby Kačna jama (Snake cave) which is 280m deep, 12,750m long, and reaches the ground water level.
The exploration took place in 1889 and the following years and cost an enormous amount of work and time.
Later he guided international speleologists into the cave and was thus mentioned in various international speleologic magazines.
The famous psychoanalyst Sigmund Freud visited Divaška Jama and was guided by Gregor Žiberna.
He was rather impressed by him and was convinced he was an unrecognized genius.